The San Francisco-based company, with more than 8 million client brokerage account and over 1 million retirement plan participants, is an example of a financial-services firm that has launched its own ETFs.

Competition in this particular space of the fixed-income ETF market includes Vanguard Total Bond Market ETF (NYSEArca: BND) and iShares Barclays Aggregate (NYSEArca: AGG).

An ETF’s expense ratio is part of the overall cost of investing in the fund, which also includes any broker commissions and bid/ask spreads.

Tisha Guerrero contributed to this article.